Tuesday, June 2, 2009

E-probe experiments

It was an interesting day in the office, I have however not managed to get much work done, shame on me! On the other hand, I had a couple of very inspiring conversations, which will gove work a boost later that month...

Back to electro-magnetic stuff.

Since the E-probe, aka PA0RDT Mini-Whip, proved itself, today it was time see what it can and cannot do.
Thus, wired up the E-probe with the HF3/W and fire up the latter. Location of the E-probe about 2m of my server (which btw also serves as grabber and WSPR-mept) running in full swing. Expecting the worst, I tuned in the following frequencies:
  1. 5450kHz RAF Volmet
  2. 3866kHz DWD weather fax
  3. 7880kHz DWD weather fax
  4. 6075kHz DW (BC-AM)
  5. 0518kHz international navtex
  6. 0198kHz BBC
  7. DCF77
  8. 0060kHz MFS
Here's the outcome of the tests (performed between 1830z and 1900z):
  1. no qrm, 57 / 59
  2. no qrm, 59+
  3. no qrm, 55
  4. no qrm, 59++
  5. no qrm, no signal (navtex is scheduled)
  6. qrm 3, 26
  7. qrm 4, 48
  8. qrm 5
Next test, swing the E-probe out of the Farraday-cage I call my house, and here's 'm results:
  1. 59+
  2. 59+
  3. 57
  4. 59++
  5. no qrm, still no TX scheduled
  6. qrm 2, 36
  7. qrm 4, 49
  8. qrm 5
Concluding, I would like to partially confirm Roelof's experience. What longwave is concerned, and that's what PA0RDT is mainly concerned about, QRM is generated inside my Farraday-cage. Yesterday's test revealed the signals from DCF77 and MSF 60kHz could be received 59 w/o qrm on from my roofdeck.
Speaking shortwave, the story appears to be different... noise generated by my sever appears not to be an issue, signals are down, by the amount one would expect from an indoors aerial anyway.

It's about time now to setup navtex and receive some Netherlands Coast Guard (Den Helder) and some Oostende Radio.
I am confident that this test will prove positive too.


UPDATE:
It's now 2110z, using the E-probe, indoors, the HF3-RX and my EeeBox, all just about 1m apart, capturing forecasts transmitted by DDH7 (7646kHz)... RST: 559

ZCZC 478
WODL45 EDZW 022100 COR
STRONGWIND GALE STORMWARNINGS FOR SEA AREAS:
GERMAN BIGHT, WESTERN AND SOUTHERN BALTIC.

GERMAN BIGHT:
GALES NORTHWEST 17 TO 19 M/S (7 TO 8 BFT).

WESTERN BALTIC:
NEAR-GALES NORTHWEST 14 TO 16 M/S (6 TO 7 BFT).

SOUTHERN BALTIC:
NO WARNING.

COASTAL AREA WARNINGS:
STARKWIND, STURMWARNUNGEN FUER DEUTSCHE KUESTEN.

NR. 246
STURM - WARNUNG DES SEEWETTERDIENSTES HAMBURG
FUER DIE DEUTSCHE NORDSEEKUESTE
HERAUSGEGEBEN AM 02.06.2009 UM 14:00 UHR GZ.
OSTFRIESISCHE KUESTE: NORDWEST 7, DABEI BOEEN VON 9 BEAUFORT.
ELBEMUENDUNG: NORDWEST 7, DABEI BOEEN VON 9 BEAUFORT.
SEEGEBIET HELGOLAND: NORDWEST 7, DABEI BOEEN VON 9 BEAUFORT.
NORDFRIESISCHE KUESTE: NORDWEST 7 BIS 8, DABEI BOEEN VON 9
BEAUFORT.
ELBE VON HAMBURG BIS CUXHAVEN: NORDWEST 5 BIS 6, DABEI BOEEN VON
8 BEAUFORT.

NR. 230
WIND - WARNUNG DES SEEWETTERDIENSTES HAMBURG
FUER DIE DEUTSCHE OSTSEEKUESTE
HERAUSGEGEBEN AM 02.06.2009 UM 22:35 UHR GZ.
FLENSBURG BIS FEHMARN: NORDWEST 6 BIS 7 DABEI BOEEN VON 9
BEAUFORT.
OESTLICH FEHMARN BIS RUEGEN: NORDWEST 6 BIS 7 DABEI BOEEN VON 9
BEAUFORT.
OESTLICH RUEGEN: NORDWEST 6 DABEI BOEEN VON 8 BEAUFORT.

SEEWETTERDIENST HAMBURG

=







NNNN

Thus, concerning my maritime needs, the E-probe does the trick.

Tests on Navtex are still pending... I will leave the setup run through the night, some reports my have tumbled in. FAX also needs to be done. I'll try to catch the 2200z-TX from DDK3 (7880kHz).

73!